Outlander co-stars Sam Heughan and Caitriona BalfeNominee: Catriona Balfe, who appears in the TV series ‘Outlander'Sam Heughan and Caitriona Balfe attend the "Outlander" Mid-Season New York Premiere after party at The Oak RoomActor Sam Heughan and actress Caitriona Balfe attend the Starz Series "Outlander" Premiere - Comic-Con International 2014A scene from Outlander.Actors Sam Heughan (L) and Caitriona Balfe attend the "Outlander" press room during Comic-Con International 2015 at the Hilton Bayfront on July 11, 2015 in San Diego, California. (Photo by Chelsea Lauren/Getty Images)

Irish actress Caitriona (xx), from Co Monaghan and the Scottish actor are famous for their onscreen chemisty as Claire Randall and Jamie Fraser, but the former model said the heat between them is strictly for the cameras.

"We're not together," Caitriona told E! News. "It's funny. We've always said from the get go that we're incredibly great friends. And to have that friendship and that closeness and to be able to get along as we do on set, it's great that we're able to get along that well. We're not together. I'm sorry to break people's hearts.

Nominee: Catriona Balfe, who appears in the TV series ‘Outlander'

"They like to try to maybe replicate the Claire and Jamie story. But I think it would be difficult for us to work together and be together."

The pair said they understand fans' hopes for a real-life romance, but reiterated they're just good friends.

"I think people buy into the show and us saying it's not real, they feel like they've been duped. It's like, ‘You acted it. You lied to us!' And I'm like, ‘Well, sorry!'"

Caitriona has been nominated for the Best Actress in a Television Drama Series category at the Golden Globes.

Sam Heughan and Caitriona Balfe attend the "Outlander" Mid-Season New York Premiere after party at The Oak Room